class Node:

    def __init__(self, value):
        self.value = value
        self.next = None


class LinkedList:

    def __init__(self):
        self.head = None

    def __find_tail(self):
        current = self.head
        while current.next is not None:
            current = current.next
        return current

    def append(self, value):
        node = Node(value)
        if self.head is None:
            self.head = node
        else:
            tail = self.__find_tail()
            tail.next = node
